238 JOUKNAL OF THE EOYAL HORTICULTURAL SOCIETY. 



point of view. On the other hand the prevalence of cloud in October 

 made night frosts rare in that month, and the result is shown in the mean 

 temperature on the grass for October being as high as it was in 

 September. 



Fio. 49. — Mean Tebiperatuke of the Air for each Month of the Year 



COMPARED WITH THE AvERAGE ; ALSO THE MeANS OF THE HiGHEST AND 



Lowest Tejiperatures obtained each Day, and of the Lowest Tem- 

 perature REACHED ON THE GrASS AT WiSLEY DURING THE YeAR 1906. 



The comparison of the march of the temperature of the soil at different 

 riepths with the temperature of the - air exhibited in fig. 3 shows a closer 



